A form of therapy used by chiropractors in their practice is spinal manipulation. This is a therapeutic intervention performed on synovial joints in the spinal column, and intended to relieve symptoms of back pain.
Known instruments for assisting with such manipulation include devices which require the chiropractor to pre-load or arm the device by pulling a handle against the action of a strong spring force. The continued use of such devices can lead to development of carpal tunnel syndrome, lateral epicondylitis (tennis elbow), or other debilitating injuries.
More recently, chiropractic adjustment instruments which use alternating current to counter the strong spring force have been developed. However, such devices have other drawbacks such as lengthy cables which may cause a trip hazard.